Bending machine



Nov. 27, 1934e G. A. HOENER BBNDING MAGHIN Filed Deo.

8, 1932 2 Sheets-Sheet 1 failli/'1" INVENTOR.

am Qo lll l l RTH* ma ll Patented Nov. 27, 1934 i 1 UNITED STATES PATENT OFFICE BENDING MACHINE Gustav A. Hoener, Detroit, Mich.

Application December 8, 1932, Serial No. 646,274

25 Claims. (Cl. 153-40) My invention relates to improvements in bendpressure member rotatably mounted on a piving machines in which the member to be bent or otally mounted member. formed is pulled from a locating member dur- I attain these objects by mechanism illustrated ing the bending or forming operation; and the in the accompanying drawings, in Which objects of my improvement are, first, to provide Figure l is a plan vievvk of the bending ma- 60 a bending machine in which the member is bent chine, disclosing a horizontal section on the line or formed with a plurality of bends extending 1 1, Fig. 4; Fig. 2, a vertieal'section of a part in different planes in one operation; second, to of the bending machine on the line 2 2, Fig. provide a bending machine for bending any kind l; Fig. 3, a vertical section of a part of the bendof metal tubing of round, square, oval, or similar ing machine on the line 3 3, Fig. l; Fig. 4, a Yc5 shape as well as various kinds of moldings or vertical section of the bending machine on the similar members; third, to provide a bending ma? line 4 4, Fig. l; Fig. 5, a partial horizontal chine which accomplishes a bending operation section through the pressure rollers disclosing a as it pulls the member to be bent from an arbor; pipe having a portion which has passed through fourth, to provide a bending machine having said pressure rollers and has been bent or formed 70 an arbor with a portion fitting wit-hin the object -to a pre-determined shape; Fig. 6, a partial verto bebent; fth, to provide a bending machine tical section on the-line 6 6, Fig. 5; and Fig. 7, having pressure members engaging the outside a vertical section on the line 7 7, Fig, 4. of the member to be bentat points adjacent a Similar numerals refer to similar parts member within the member forabsorbing the throughout the several views. 75 thrust load developed during the bending opera- The base portions l of the bending machine tion; sixth. to provide a bending machine having are supported on the floor 2 and the table or a revolving fixture plate: seventh, to provide a housing 3 is suitably secured to and supported on bending machine having a revolving xture plate the flanges 62 of the base portions.

of irregular outline with teeth members around The housing 4 is suitably secured to the table 80 its irregular periphery; eighth, to provide a bend- 3 by the fiange 5 and the bolts 6, the housing 4 in,r machine having a revolving fixture plate being provided with the flange 7 which fits over operated by an elastic drive means; ninth, to the edge of the table 3 to relieve the bolts 6 from provide a bending machine having a pair of fiexcarrying the total weight of the housing 4. The

ibly mounted pressure rollers for developing bendhousing 4 is providedwith the boss 8 to which ing pressures: tenth, to provide a bending mais secured the flange 9 of the electric motor 10, the chine having a revolving fixture plate provided flange 9 being secured to the boss 8 by the bolts 1l. with a plurality' of fixture members for support- The electric motor l0 is provided with and. oper-` ing a plurality of members to be bent; eleventh, ates the shaft 12 to which is suitably secured the to provide a bending machine having a xture worm 13 which engages and operates the Worm 90 plate provided with a rim portion of uniform gear 14 which is secured to the shaft 15 by the width for engaging driving and stabilizing memkey 16. The shaft l5 is rotatably mounted in bers; twelfth, to provide a bending machine havthe boss 17 of the table 3. The gear 18 is secured ing a fixture plate adapted to travel alternately to the shaft 15 by the key 19 and is adapted to in straight lines and then along a radial path; rotate with theshaft 15 and the Worm gear 14. 95 thirteenth, to provide a bending machine lhav- They worm gear 14 and the gear 18 are also ing a flexible means for driving a fixture plate secured on the shaft 15 by the nut 20 and key 19 together with means for maintaining the flexand the Washer 21 which hold the Worm gear ible drive means in a taut position adjacent the 14, the gear 18, and the shaft 15 in their proper,

fixture plate; fourteenth, to provide a bending operative positions with the Worm gear 14 and 100 machine having a fixture member adapted to the shoulder 22 ofthe shaft 15 respectively held pass, with the member to be bent, between a pair against the end surface of the boss 15 and the of pressure rollers; fifteenth, to provide a bendupper surface 28 of the table l. ing machine having a fixture member constructed The gear 24 is secured to the shaft 25 by the with flexible mounted sections; sixteenth,` to key 26, the shaft 25 extending through and being 105 provide a bending maChne having 1 XtllY@ plate rotatably mounted in the boss 26. The sprocket adapted t0 mOVS in a Single plne and haVIig 27 is also secured to the shaft 25 by the key 28,

portions adapted to be deflected from the plane the gear 24 and the sprocket 27 being secured in of movement of the fixture plate; and seventheir proper operative positions by the nut 29 and teenth, to provide a bending machine having a the washer 3c holding the gear 24 against the 110 end surface of the boss 26 and the sprocket `2'? on, the chain 34 beingdriven by the sprockets 27 to further drive-the sprocket 33 which acts as anA idler sprocket.

The shaft 32 is provided withthe shoulder 35 to retain .the sprocket 33 in its-"proper operative f position relative tothe upper surface 23 ofthe table 3.

The fixture plate or housing 36 is provided with the internal surface 37 whichis adapted to en- 39 being engaged by the chain 34 which. thus causes the fixture plate 36 to travel past the roller `38, thel fixturefplate 36 thusbeingactuated to' follow a line of movement which is determined bythe shape or outline of the fixture vplate 36,v the fixture plate 36 thus alternately traveling in straight lines and then revolving'about the centerv of the roller 38-.as the irregulark shaped portions, such as the corners of the fixtureplate 36, take their positions adjacent the roller38, the irregular outline or shape of the fixture plate 36 4being determined by the desired shape of the objectto be bent or formed.

It is to be noted that the widthJ of the rimportion 40, of the fixture plate 36,`between the pitch.` line of the sprocket teeth39 andthe.suriace137,: will be maintained the same throughout the length of said rim portion 40.

It is also to be noted that the sprocket teeth 39, of the fixture plate 36, will forni sprocket lrack portions on the straight .sidesand portions of sprocket gear portions at the-comers of the fix.-' ture plate 36, the actual outline or shape'of thev fixture plate 36 and its sprocketrteethportions variations of the fixture plate disclosed as may be required to produce any desired shape .or-form.

of an object to be bent orfformed.v

The rim portion 40 is provided with recesses 41 for retaining therollers 42`which thusprovideir anti-friction bearing members between the kfix.v

ture plate 36 and the surface .23 of the tablef3,

the proper operating space 43 `being maintained f between the fixture plate v36 `and the surface'23l.

of the table 3.

The idler sprockets 64 and 44 are lmounted on the levers 45, one of which is disclosed inFig; 2,`

the levers 45 beingadapted to oscillate on .the bearing portions 46 ofV the studs 47 whichmay be threadably secured in the bosses 48 of .tablef3, theV levers 45 being .retained on. the studs 47 "by the shoulder portions l49`of the studs 47.` The idler sprockets 64 and 44 are rotatably mountedK4 side portion of the chain. 34 and thustake up any slack in the chain 34 von its outside. portion and maintaining its inner portion, between the sprocketsv27 and'33, in ka taut or "tightened-'po-4 sition to properly engage andeliminate any-lost-v motion between the chain'v34 and'thefsprocket teeth 39 on thefixture plate l36,:.theflevers` .45.

being locked in their, proper positions by 'screwing `chamber 53o! the housing 4.` gage the roller 38, as hereinafter disclosed, the H fixture plate 36 being provided with the `sprocket teeth 39 around its periphery, said sprocket'rteeth the studs .47- down to the` position which" will hold.. f the levers 45 in their said proper positions.

The housing 4 extends upwardly sandfisprovided withA the portion 63 whichfextendsv inwardly over '.the table 3,' the portion 63tbeing provided with the chamber 53 in which is slidably mounty edthe head member 54, the head member 54 and: the chamber 53 being of a shape as will .absorb any vtransverse thrust load .reaction developed Ain the. :bending or forming operation hereinafter described.v \The Vhead member 54fisV provided with theextension portionf 55, which'extends through .the opening 56 in the lower wallof the f The lextension portion-55, of the head member 54,.is.pr.ovide`d.

with the boss 57 in 'which is secured the 'shaft 58 byithe nut 59, the pressure roller 6G being rotat.-

ably'mounted onthe shaf-t 58 between Vthe face l' of the boss` 57 and the. shoulder Yportion 67 ofthe l* shaft 58pl The extension portion 55 :is lfurther. provided .with the vboss 68 in vwhich isl suitably securedthe shaft 69 von which is pivotally.mounted thel lever 70 on which is rotatably mounted the.l pressurerroller v71 which isI suitably retained-be. tween the yshouldered vportions. 72 vand1-73 oft .the leiver' 70`. The lever 70 is provided with." the arm 74which is suitably vsecuredthereto,l the: arm 74 being provided with theV shaftf75,which.is

suitably secured in the arm .74 by the nut176`.. The. l:

roller 77 ,is rotatably mounted onrthezsh'aft :1751" between .the face of the arm 74 and the 'shoulde'rv` portion78 of thev shaft 75.

The guide members'79 areA constructed with the same. form or outline as therim portion40v ofv the. fixture plate 36 andare each provide'dlwith the surfacer80 for contacting the. roller 77, the guide. members 79 being vfurther -providedwith the. brackets 81 vwhich are fastenedto the. rim portion 40 vof the fixture plate 36 by thescrews 82."v

They fixture or form membersA .83' are con'- ber is to be bent or formed and Yare arrangedmo extend parallel with `and adjacentthe. guide. members 79, the fixture memberst83 vbeing prof -vided with a curved'portion 84` which fits andrenr r gages with the groove 85 in .the ipressure roll-1 er v71.^`

Itis to be noted thatfwhereas my bending .mae chine-is adaptable for bending any kind rof `hol-,H low or tubular members Whether round, oval, squareor other shape and also various kinds and,v shapes of mouldings and similar members ini. one operation, I .have disclosed themachine `as operating on a pipe 86 of usualconstructionas this will more easily and clearly-disclose the op-fv erationfof. my invention.. The pipe 86 ffits be tween and engages the groove 87. of the pressure roller4 66 fand the grooves 88 of the fixture members 83.

The pipe 86 is placed or telescoped vfoverthe arbor -89 which isprovided'with the balliportion 90 whichv fits within the inside surface of the pipe 86.

The roller 38 is rotatably mounted on the shaft;

91 Which-is suitably secured in lthe lever-192 by 140y in :the-:table 3, the lever 92 being further-con#- 145.."

nectedwith the shaft 96`by means of'r a swivelly' mounted member .97 vsuitably. `secured in the lever 92,the. outer end of the shaft 96 being rotatably mountedfin the bracket 98 which is secured to` It vstructed of the desired shape to. whichethe membeing possibe of construction to meet any desired the table4 3 by the screws 99, the shaft 96 `being 15u :nasales provided with the handwheel 100 for manually operating the shaft 96.

It is to be noted that the operation of the handwheel 100 will cause the lever 92 to move the roller 38 into Contact with the internal surface 37 of the fixture plate 36 which will in turn force the teeth 39 into engagement with the chain 34 and at the same time the surface of the guide mem.- ber 79 will be forced into engagement with the roller 77. 'Ihe thrust of the guide member 79 against the roller 77 will cause the lever 70 to pivotally move to force the pressure roller 71 into engagement with the curved portion 84 of the iixture member 83 which will cause the pipe 86 to be gripped between and within the groove 88 of the fixture member 83 and the groove 87 of the pressure roller 66, the pipe 86 being thus gripped at points opposite the ball portion 90 of the arbor 89, the ball portion 90 absorbing the thrust of the pressure against the outside surface of the pipe 86 during the bending or forming operation, the spherical surface of the ball portion 90 allowing the pipe 86 to bend and form to the shape or form of the fixture members 83.

'It is to be noted that the above mentioned movement of the lever 92' and the roller 38 will be possible due to the formation of the slot 101 in the table 3 which will permit the shaft 91 to move within said slot 101.

It is also to be noted that the head member 54 will be actuated to a position in which the pressure roller 66 will grip the pipe 86, in conjunction with the xture member 83, by means of the shaft 102 which is supported in and threadably engages the boss 103 of the housing 4, the inner end of the shaft 102 being connected to and supported in the member 104 which is slidably mounted in the bore 105 of the portion 63 of the housing 4, the-member `104 forming'a retainer member for the spring 106 which extends within the recess 1 07 of the head member 54, the shaft 102 being lprovided with thel handwheel 108 for manually operating the shaft 102.

The operation of the handwheel 108 and shaft 102 will cause the member 104 to exert a force tending to compress the spring 106 and force the head member 54 to move toward the fixture member 83, the spring 106 always permitting the pressure roller 66 to free itself when necessary or to adjustably accommodate itself to the necessary positions required when bends or irregular shapes are being formed in the pipe 86.

Also the actuation of the pressure roller 66, by means of the spring 106 against the head member 54, together with the actuation of the fixture member 83, by means of the pressure roller 66 and the fixture member 83 to be separated slightly When the pipe 86 is initially entered therebetween, the pressure roller 66 and the xture member 83 being immediately returned to positions, in which they firmly grip the pipe 86, by means of the .manual operation of theroller 38.

It is to b understood that the operation of bending and forming a member to any desired shape in my bending machine is accomplished rst by placing the member, which in the present disclosure, is the pipe 86, on the arbor 89 with the ball portion 90 on the inside of the pipe 86 at a point between the pressure roller 66 and the xture member 83, this being readily accomplished by inserting the end of the pipe 86 and the ball portion 90 therein between the pressure roler 66 and the fixture member 83, the spring 106 allowing the gripping members to slightly separate, if necessary, said gripping members immediately resuming their gripping hold on the pipe 86 which securely holds the pipe 86, and as the fixture plate 36 is actuated infits travel movement by the chain 34, the pipe 86 will be pulled from the arbor 89 and over the ball portion 90. In order to secure the arbor 89 from moving or traveling along with the pipe 86, the arbor 89 is provided with the head portion 109 which engages the jaws 110 of the table 111 which is slidably mounted on the ways 112 of the table 113 which, in turn, is slidably mounted on the ways 114 of the table 116 of the bracket 115 which is secured, by the bolts 144, to the table 3, in a manner similar to the housing 4. The arbor 89 fits between the jaws 110 of the table 111 and is easily removed for insertion within a pipe 86, the fixture plate 36 being provided with a pair or more of iixture members 83, so that the pipe 86, after bending or forming, may be removed from one of the fixture members 83 while another nxture member 83 and the pipe 86 are passing between the pressure roller 66 and a iixture member 83.

The table 113 is providedwith theshaft 117 which is suitably mounted therein and adapted to engage and move the table 111 when the handwheel 118 is manually operated. The table 116 is provided with the shaft 119 which is suitably mounted therein and adapted to engage and move the table 113 when the handwheel 120 is manually operated. The position of the jaws 110 can be thus readily adjusted to accommodate various lengths of arbors and pipes and to provide the proper position of the arbor 89 and the pipe 86 relative to the fixture members 83. The fixture members 83 are provided with brackets 121 which are provided with flanges 122 by whichsaid iixture members 83 are secured to the iixture plate 36 by the screws 123.

It is also to be noted that when it is desired to form the pipe 86 with a bend extending at an angle with the horizontally extending xture plate 36, the xture members 83 will be provided with the sections 124 and 125, or similar sections, which are pivotally connected to one another by the pins 145, the sections 124 and the adjacent portions 126 and 127 of the fixture members 83 being provided with the inclined sides 128 to permit the sections 124 to pivotally move and travel along a path or line of movement extending at an angle with the face of the fixture plate 36. The sections 124 are provided with bosses 129 which pivotally move within similar shaped recesses 130 in the sections 125 and also in the portions 126 and 127 of the fixture members 83. The sections 125 and the portions 126 and 127 of the iixture members 83 are provided with 'the extension portions 131 which are adapted to contact with the sides of the sections 124 and prevent the pivotal movement of the sections 124 beyond a pre-determined amount thus insuring that the sections 124 and 125 will never move beyond an aligned position. in one direction, parallel with the face of the xture plate 36 and at the same time allowing the iixture members 83 to be. guided to the required position necessary to accommodate the desired bend or form with which the pipe 86 is to be constructed.

In order to actuate the xture members 83 to the required positionto which the pressure roller 66 and the fixture members 83 will bend or form the pipe 86, the portions 127 of the fixture members 83 are each provided with the arms 132 having the bosses 133 in which is suitably secured the pin cr shaft 134 on which is rotatably mounted the roller 135 which is suitably retained in a slot in the bosses 133, the pins 134 being provided with the shoulder portions 136 and with the cotter pins 144.

The guide member 137 is provided with the surface or cam portion 138 with which the roller 135 contacts, thereby causing'the fixture member 83 to be displaced to the required position for the pressure roller 66 and the fixture members 83 to form the desired shape of the pipe 86. The guide member 137 is provided with the fianges 139 through which extend the screws 140 for securing the guide member 137 to the fixture plate 36, the guide member 137 being located on the fixture plate 36 at the proper position so that when the roller 135 contacts therewith, the pipe 86 will be bent or formed with the required bend or form located in the desired position on the pipe 86.

The electric motor 10 may be suitably oonnected with a source of electric current and may also be connected, by the wires 141 and the wires 142, to the switch assembly 143 suitably located at the front of the table 3'for convenience of the operator in controlling the operation of the bending machine.

It is also to be understood that the bending machine may be power operated by sprocket and chain means or other elastic drive or similar driving means.

I claim:

1. In a machine for bending a pipe, the combination of a supporting base provided with a table, a fixture plate movably mounted on the table of said supporting base, said fixture plate being provided with a rim portionhaving-tooth projections around its periphery, fiexible driving means engaging the tooth projections of said fixture plate, a movably mounted head member, av

pressure roller revolvably mounted on said head member, a lever pivotally mounted on said head member, said lever being provided with a roller for engaging portions of said fixture plate, a second pressure roller revolvably mounted on said lever, fixture members mounted on said fixture plate, said fixture member engaging said second mentioned pressure roller, said fixture member being adapted to co-operate with said first mentioned pressure roller to bend the pipe, an arbor within the pipe, said arbor being provided with a ball portion located adjacent said first mentioned pressure roller, means for supporting the outer end of said arbor, manually operated means for actuating said fixture plate to engage the roller of said lever, and manually operated means for moving said movably mounted head member.

2. In a machine for bending a member, the combination of a movably mounted fixture member having an irregular shape, said fixture member being provided with tooth projections, said fixture member being provided with a pressure member for engaging the member to be bent,re volvably mounted members oppositely disposed about and respectively engaging the pressure member of said fixture member and the member to be bent, anddriving means engaging the tooth projections "of 'said movably mounted fixture member.

3. In a machine for bending members, the combination of an arbor within the member to be bent. said arbor being provided with a spherical portion at its inner end, means for supporting said arbor at its outer end, and means for applying pressure against the outside of the member to be bent fat points adjacent the spherical surface of said portion of said arbor, said means comprising a fixture member suitably mounted to move about an axis and transversely relative to said axis.

4. In a machine for bending a member, the combination of means for supporting the member to be bent on an arbor, and means for bending the member, said means pulling the member off of said arbor during the bending operation, said means comprising a fixture member suitably mounted to move about an axis and in a plane extending transversely relative to said axis.

5. In a machine for bending members, the combination of means for applying pressure against the member to be bent, and a revolvably mounted fixture member engaging said means and the member to be bent, said revolvably mounted fixture member being provided with a plurality of irregular shaped portions for alternately engaging said means.

6. In a machine for bending members, the combination of pressure applying members. and a fixture member having portions traveling between said pressure applying members, said fixture member alternately traveling in a straight path and in a curved path.

7. In a machine for bending members. the combination of a movably mounted fixture plate, a fixture member mounted on said fixture plate, said fixture member being provided with sections movably connected relative to one another, a

roller member suitably mounted on said fixture f member, and a guide member suitably mounted, said guide member engaging said roller to cause said fixture member to be moved from its normal position to enable the machine to form a bend in l fixture plate, pressure developing members. and a fixture membeiysuitably mounted on said fixture plate, said fixture member having a portion engaging one of said pressure developing members together with the member to be bent.

10. In a machine for bending a member, the combination of a table, means for bending the member in the plane of said table, and means for bending the member along a line extending at an angle with the plane of said table, said last mentioned means bending said member after it has passed through said first mentioned means.

11. In a machine for bending a member, the combination of an arbor for supporting the member to be bent, said arbor extending within said member to be bent, means forsupporting said arbor, and means for adjustably changing the position of said first mentioned means in longitudinal and transverse directions.

12. In a machine for bending a member, the combination of an arbor for supporting the mem" ber to be bent. and a member provided with open jaw portions for supporting said arbor. said arbor being supported between the open jaw portions of said last mentioned member to permit ready removal of said arbor therefrom.

I3. In a machine for bending a member, the combination of an arbor for supporting the member to be bent, means for bending the member, said means pulling the member off of said arbor during the bending operation, and means for anchoring said arbor to prevent longitudinal movement of said arbor,.said second mentioned means comprising a member having an open portion adapted to receive said arbor therethrough to permit ready insertion or removal of said arbor relative to said'second mentioned means.

14. In a machine for bending a-member, the combination of a movably mounted fixture plate having a rim portion extending peripherally therearound, said rim portion having an equal overall width throughout its length, a roller suitably mounted, and means for causing said roller to engage the inside surface of said rim portion, and driving means engaging the rim portion of said xture plate.

15. In a machine for bending a member, the combination of pressure members located on opposite sides of the member to be bent, said pressure members constituting the sole means for clamping said member during the bending operation and means for causing said pressure members to form the member to be bent.

16. In a machine for bending a member, the combination of pressure members, a fixture member provided with movably mounted sections having means for limiting the movement of said sections beyond a pre-determined position, and means for moving said sections to allow s aid pressure members to form a bend in the member to be bent.

17. In a machine for bending a member, the combination of a fixture member movably mounted and having a rim portion of substantially uniform Width throughout its length, means for driving said fixture member, said means operatively engaging said rim portion at one of its sides, means for resisting the thrust of said first mentioned means, said last mentioned means being oppositely disposed from said first mentioned means relative to said rim portion, and means suitably mounted and cooperating with said fixture member to bend said member.

18./In a machine for bending a member, the combination of a fixture member, means suitably mounted and cooperating with said xture member to accomplish the bending, and means for actuating said xture member to move about an axis during a portion of its movement, said xture movement being actuated to move transversely relative to said axis during a portion of its movement.

19. In a machine for bending a member, the combination of a fixture member movably mounted, said fixture member having a rim portion, means suitably mounted and cooperating with said xture member to accomplish the bending, driving means for actuating said fixture member, and means cooperating with said driving means to guide the rim portion of said fixture member to travel around a plurality of axial points.

20. In a machine for bending a member, the combination of revolvably mounted means, a xture member provided with a plurality of members adapted to alternately cooperate with said revolvably mounted means to accomplish the bending, and means for actuating said fixture member.

21. In a machine for bending a member, the combination of a fixture member movably mounted and provided with a rim portion, means engaging said rim portion to drive said xture'member, revolvably mounted means oppositely disposed to said Iirst mentioned means about said rim portion to absorb thrust reactions, and means cooperating with said fixture member to accomplish the bending.

22. In a machine for bending a member, the combination of means for supporting a member to be bent, and a pair of pressure means movably mounted and engaging the member to be bent, one of said pressure members being further adapted tomove past the other of said pressure members, said pair of pressure means constituting the sole means for clamping said member to be bent, said pressure means causing the member to be bent to be moved relative to said first mentioned means.

23. In a machine for bending a member, the combination of a pressure member revolvably mounted and engaging the member to be bent, a fixture member exerting pressure, in cooperation with said first mentioned pressure member, to bend the member being operated on in agiven plane, said second mentioned pressure member being adapted to move past said rst mentioned pressure member, means operatively connected with said fixture member and controlled by the movement of said fixture member to cause the member being operated on to be bent in one or more different planes from said rst mentioned lplane, and means for actuating said fixture mem- 24. In a machine for bending a'member, the combination of bending means engaging opposite 'sides of the member to be bent, an arbor member extending within the member to be bent and having a portion engaging inside surfaces of the member substantially in alignment with said bending means, said arbor member being provided with a shoulder portion at its other end, a supporting member having a recess for receiving said arbor member, the shoulder portion of said arbor member engaging a surface of said supporting member to.restrain said arbor member from moving longitudinally, means for adjusting said supporting member to cause longitudinal' movement of said arbor member, and means for adjusting said supporting member to cause transverse movement of said arbor member.

25. In a machine for bending members, the combination of revolvably mounted means adapt-A ed to engage the members to be bent, a fixture member suitably mounted and adapted to exert pressure on the members to be bent, said fixture member being provided with teeth extending in curved and in substantially straight paths, and driving means engaging the teeth of said fixture member, said xture member being actuated to move along an irregular path.

GUSTAV A. HOENER. 

